#include<iostream>

#include"head.hpp"

int GetSum(int n){
  int ret = 0;
  for(int i = 1;i<=n;++i){
    ret+=i;
  }
  return ret;
}

int main()
{
  int n =10;
//  std::cin>>n;
 
  int arr[] = {6,7,8,9,1,2,3};

  int ret = GetSum(n);
  std::cout<<ret<<std::endl;

  Cout(666);

  return 0;
}
